WABCO SYSTEM SAVER HP MM1736, Maintenance Manual

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15
Component Removal and Installation
EN
Table B: Replacement Requirements
Component When to Replace Why
Cartridge Every two to three years for standard
dessicant.
Every one to two years for coalescing.
Preventative maintenance.
When compressor is replaced. Contaminated cartridge.
Water in supply tank. Saturated or contaminated cartridge,
high duty cycle (wrong application of
air dryer).
Heater
Assembly
Water collecting in air dryer is freezing —
electrical power to dryer is OK. Heater assembly not working
(internal short or open circuit).
Outlet Check
Valve
Air continues to flow from purge valve after
purge cycle, but stops flowing when the
compressor load cycle begins.
Valve is stuck in the open position, or
not functioning correctly.
No pressure build-up in system, everything
else is OK.
Valve is stuck in closed position.
Purge Valve No purge cycle when compressor unloads
— normal pressure at dryer control port 4
(governor port).
Valve is stuck in the closed position,
or not functioning correctly.
Air flows from purge valve during
compressor’s load cycle — no pressure at
dryer control port.
Valve is stuck in the open position, or
not functioning correctly.
Turbo Cut-Off
Valve
Air compressor stuck pumping, TCU remains
open. System will build pressure until safety
valve opens in system.
Signal line loss.
Air flows from purge valve during
compressor unload cycle after purge cycle,
and flow is noticeably stronger at high
engine RPM, especially under load.
Turbo cut-off valve leaking.
No pressure build-up in system — high
compressor discharge line pressure.
Valve stuck in closed position.